Abstract
BACKGROUND: Atrial fibrillation (AF) is common in intensive care and often complicated by acute kidney injury (AKI). The triglyceride-glucose (TyG) index, a marker of insulin resistance, has not been studied for AKI risk in AF patients. METHODS: This retrospective cohort study analyzed 1,142 critically ill AF patients from MIMIC-IV. Patients were stratified by TyG index tertiles. Multivariable logistic regression, restricted cubic splines, and ROC curves assessed the TyG-AKI relationship, adjusting for confounders. RESULTS: AKI incidence was highest in the top TyG tertile (52.76%) versus middle (37.20%) and lowest (36.39%) (p < 0.001). After adjustment, higher TyG (continuous) correlated with increased AKI risk (OR 1.21, 95% CI 1.02-1.45, p = 0.002). The highest tertile had greater AKI risk than the lowest (OR 1.37, 95% CI 1.29-2.02, p = 0.02). Spline analysis showed a near-linear dose-response relationship. The ROC AUC was 0.77, indicating moderate predictive value. Subgroup analyses confirmed consistency across age, sex, ethnicity, and comorbidities. CONCLUSION: Elevated TyG index independently predicts higher AKI risk in critically ill AF patients, with a near-linear association. The TyG index may aid AKI risk stratification in this population.